Study subjects seen to date to better understand the immune pathogenesis of asthma in young children. Through this protocol, we have obtained the following on each study subject: 1) physical exam, 2) prick allergy skin testing to common inhalant and food allergens; 3) blood donation for serum IgE, Eosinophil Cationic Protein levels, and detailed cellular immune studies; and 4) medical records coding. Progress during the first year of this 5-year protocol has met expectations for recruitment, and exceeded expectations in preliminary data for immune pathogenesis studies. This data has substantiated 5 abstracts that have been accepted for presentation in 1999 at several different national meetings. Our plan is to continue these immune studies for the remainder of the study subjects to substantiate our preliminary findings, and to determine if these early immune findings may serve as predictors for the development of asthma and allergen sensitization.